Regulator for pulverizing mills



Oct. 19 1926.

, J. cRlEs ET ALj REGULATOR FAOR PULVERIZING MILLS Filed March 2 ,i 1925l I aieaa1i. ia,

JOE CRITES, OF EVANSTON, AND WILLIAM H. VOGELVOF HIGHLAND PARK,ILLINOIS, i

ASSIGNORS '10 RAYMOND BROTHERS IMPACT .'PULVERIZER CO., OF CHICAGO,ILLI` NOIS, A CORPORATION OF ILLINOIS.

REGULATOR FOR PULVERIZING MILLS.

Application filed March. 21925. SeriaIiNo. 12,678.

This inyention relates' to means for pulverizing fue-l, and moreparticularly to improvements in a pulverizing mill of the impact type,in which a plurality of swinging hammers operate Within a substantiallycylindrical beater chamber.

The principal objectv of theinventon is to provide improved means foradjusting the fineness of the pulverized material produced, such meansbeing accessible for adjustment from outside the mill, withoutnecessarily stopping the operation of the mill; j

More specifically, a rotary regulator is interposed between the beaterchamber and the fan chamber of the mill, which acts to retard more orless the passage of coarse material from the beater chamber to the fanchamber. A normally stationary conical ring which surrounds this rotaryregulator, is adjustable toward or from the regulator by means which arereadily accessible from outside the mill, thus varying the operation ofthe regulator, and determining `its retardn ing influence upon thematerial in the air passing therethrough.

The above and lother objects and advantages of this invention will bemore apparent from the following detailed description of one approvedform of the apparatus.

In the accompanying drawings:

Fig. 1 is a central vertical longitudinal section, partly in elevationthrough tlie main portions of the mill. j

Fig. 2 is a transverse vertical section taken substantially oir the line2--2 of Fig. 1.

Fig. 3 is a perspective view of the conical adjusting ring.

The mill, as here shown, is of the wellknown impact type, and comprisesa feeding compartment 1, a beater chamber 2 in which the pulverizationprocess takes place, and a fan chamber 3. A horizontal shaft 4 extendscentrally through the substantially cylindrical chambers 2 and 3, and isrotat ably supported at its ends, outside of the chambers, in bearings5` and 6. One projecting end 7 of shaft 4 is conncctedwitlan electricmotor or other suitable driving means. l/Vithin the beater chamber 2,the pulverizing mechanism 8, hereinafter more specifically described, isfiXedly mounted on rotary shaft 4, and a fan 9 is similarly mounted onshaft 4 Within the fan chamber 3.

The material to be pulverized is maintained within a hopper or otherstorage receptacle, the lower end of which is indicated at 10, and theflow of material from this receptacle into feeding compartment 1, isregulated by the slide valve 11. Below the valve 11, a. fpocketed feedwheel'12 is mounted on a sha t 13 to rotate ina clockwise direction,Fig. 1, and thus steadily feeds measured quantities of the material into'the lower portion of feeding compartment 1 and thence through inletopening 14 into tlie inlet end of beater chamber 2. The shaft 13 isinter mittently driven at an adjustable slow speed, by a mechanism notshown, from the shaft 15 in the loiver portion of the .mill housing,which shaft 15 is driven through suitable reduction gearing and the belt16 from' the main rotary shaft 4.

The pulverizing mechanism 8 comprises a plurality (here shown as threeduplicate'i'adial series). of beaters or'liammers 17, pivotally mountedat their inner ends 18 for limited swinging movement. within a frame orspider composedl of a series of plates or discs 19 keyed on shaft 4.These plates 19 are spaced apart by rings 20. and are clamped inassembled position with-the rings 20 upon shaft 4, between the fixedcollar 21 on said shaft, and a nut 22 adjustable ,along said shaft 4.Suitable liner members (not here shown) are preferably arranged aboutthe path of travel of hammers 17, and within the enclosing wall of thebeater chamber 2, and the material is pulverized partially by the'impact of the hammers 17, and partly by being projected by centrifugalforce against these liner members.

The fan 9 withdraws the pulverized material suspended in air from beaterchamber 2 througli'the outlet opening into fan chamber 3, and projectsthis fuel-laden air through conduit 24 to a suitable storage bin ordirectly .to the burners where it is cousumed. Air is supplied to thebeater chamber 2, from the inlet pipe 25 and through feeding'compartment 1, and additional air may be supplied to fan chamber 3through an adjustable inlet opening 26.

lvounted on shaft 4 adjacent the opening 23 between beater chamber 22and fan chamber 3, is the rotary regulator 27, comprising a centralspider and a series of radially disico I, posed plates 28. rIlle ends ofthese plates 28 are Vpreferably inclined as shown' at 29,and

positioned to-travel within a short distance 'of thefinner face'of theconi-calming: 30,

which forms the inner' directing 'wall of out# let-23. The-action ofthis regulator isipto reduce very materially the amountof coarsematerial vinthe air passing through outlet 23 into the fan chamber.This'regulator 'acts as a fan for continuing the rotary movement ofthecontents ofbeater chamber 2 aboutl the axis of 'shaft 4, and bycentrifugal force throws the material against the diagonally disposedface of ring 3() from which it is i thrown back into the beater chamber.The

amount of coarse material in the air entering the 'fan chamber 3 fromthe lbeater chamber 2, is consequently verylsmall as compared wth theamount that would pass were this 'regulator 27 not used.

In previous mills of this general type,

.the o eration of the regulator 27 has'been varie by adjusting theregulator along shaft 4 toward or from the fixed conical ring 30. Thisof necessity involves stopping the mill and opening the same order toget at .the regulator 27 which is vcompletely en-.

closed by the mill housing.

According to the present invention, this adl justment of the retardingeffect of the regulator, Aaxially of shaft 4.

. lator is obtained by leaving the regulator 27 in fixed position on theshaft-4, but moving the conical ring 30 toward or from the regu- Theconical surface 3 0 is provided on the inner side of an annularl frame31, .the cylindrical outer periphery of which fits snugly within acorresponding cylindrical passage 32, in 'the mill housing 33. Outletopening` 23 is'provided inthe base of frame 31adjacent the smaller endof conical surface 30. A plurality, here shown as three, of diagonallyarranged slots 34 are provided in the 'cylindrical peripheral surface ofannular member 31, and suitably fixed lugs, such as the projecting ends35 of screws 36, are engaged in these slots 34. The screws 36 mayconveniently be mounted in the mill housing 33.'

It will. be noted that if the annular'member i 31 be rotated 'through asmall arc, the lugs 35 and slots 34 4will functionv as cams orscrewthreads,.to move the ring 31 to and fro axially of shaft 4, alongthe passage 32. To conveniently accomplish this movement y.of annularmember 31, a lug 37 isprovided on this annular member which projectsbetween the inner ends of a pair of adjusting screws-38, mounted in lugs39 of the fixed mill housing 33. lly suitably adjusting the screws 38which, are readily Yaccessible from outside ofthe mill, the lug 37 andconsequent] the -ring 31 may be rotated through a sma lnarc, thuslmoving the conical surfacev 30 toward or from the-ends 29 of the blades28 of the rotary regulator 27. Obviously, when the conical ring 30 isadjustedl toward the'left, Fig.' 1, that is, closer to lthe regulator27, it willl be more dificult for the coarse materialto pass therebywithout being thrown. out against theconical ring 30 fand thence back into the beating zone of the mill, andthe fuel willbe pulverized morefinely by reason ofits beingretained a'much longer time in thebeater-chamber2. By ad- A.

j usting the conical ring 30 towards the right, Fig. 1, away fromregulator 27, the pas-- sage of material thereby isf'facilitated, and

the fineness of the pulverized material correspondingly decreased. j

' It will be apparent that these adjustments may be made withoutdismantling the mill, and even without stopping the operation thereof.vByl properly proportioning .and positioning the slots 34 and the llugs35 the longitudinal movement of ring 31 axially of shaft 4 may be solimited that it is impossible to bring the ring 30 into contact with therotating blades 28 and hence there is no possibility' of injury to theapparatus even though the mill is in continuous operation. i

. We claim:

l. A. pulverizing mill comprising a beater chamber having an outlet forthe pulverized material, a rotary regulator mount ed within the chamberadjacent the outlet, and means surrounding the regulator within theoutlet and adjustable from outsidev mounted adjacent the outlet, and aring member having a conicalv opening surrounding the regulator andadjustable toward or from same to vary the flow of material past theregulator.

4. In a pulverizing mill comprising a beater chamber having an outletfor the pulverized material, a regulator of fixed dimensions -positionedwithin the outlet for retarding the flow' of pulverized material through"the outlet, and means adjustable from outside the chamber for varyingthe effective size ofthe outlet with relation to the retardingregulator.

5. In a pulverizing mill comprising a beater chamber having an outletforthe gulverized material, a rotary regulator of Xed diameter positionedfor rotation with in the outlet for retarding the flow of pulvelzedmaterial through the outlet, and

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means vadjustable frvn .outside the chamber for varying the ar.. larclearance between the rotary regulator and the surroundingy walls of theOutlet 6. #In a l,pul'verizing mill comprising a beater chamber havingan outlet for the pulverized material, a rotary regulator mountedadjacent the outlet, a ring member mounted in the outlet and having aconical opening surrounding the regulator, and means for rotating thering in the outlet and thereby moving same laterally toward or from theregulator.

7. In a pulverizing mill comprising a beater chamber having au out-letfor the pulverized material, a rotary regulator mounted adjacent theoutlet, a ring memberl mounted in the outlet and having a conicalopening and surrounding the regulator, cooperating cam means on the ringand stationary mill-housing whereby rotary movement of the ring willcause the ring to be moved laterally toward or from the regulator, andmeans accessible from outside of the chamber for rotating the ring,

8. In a 'pulverizing mill comprising a beater chamber having an outletfor the pulverized material, a rotary regulator mounted adjacent theoutlet, a ring member mounted in the outlet and having a conical openingsurrounding the regulator, there being a plurality of inclined slots inthe peripheral surface of the ring, and a Llll plurality of fixed lugsprojecting into these slots, 'whereby a partiall rotary movement of thering will cause a lateral movement thereof toward or from the regulator,and means accessible 4from outside vthe mill for rotating the ring.

9. A pulverizing mill comprising a beater chamber, a shaft vextendingcentrally therethrough, a pluralityof pulverizing 10. A pulverizing millcomprising `a beater chamber, a shaft extending centrally therethrough,a plurality of pulverizing hammers mounted on the shaft, the material tobe pulverized being fed into one ortion of the chamber, the chamberhaving an outlet around the shaft at one end thereof,

means for withdrawing the pulverized material suspended in air throughthis outlet, a rotary regulator mounted on .the 'shaft adjacent theoutlet, and a ring member surrounding the regulator and adjustabletoward or from same to vary the retarding effect of the regulator.

rough this outi ll. A pulverizing mill comprising a beatl er chamber, ashaft extending centrally therethrough, a plurality of pulverizinghammers mounted on the shaft, the material to be pulverized being fedinto one portion of the chamber, the chamber having an outlet around theshaft 'at one end thereof, means for withdrawing the pulverized.material suspended in air through this outlet, a rotary regulatormounted on the shaft adjacent the outlet, and a ring member having aconical opening surrounding the regulator and adjustable axially of theshaft to vary the retarding edect of the regulator.

JOE CRITES. WILLIAM H. VGEL.

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